Industry Foundation Classes (IFC)

From Industry Foundation Classes IFC 4.3

Introduction

The Industry Foundation Classes (IFC) are an open international standard for sharing Building Information Model (BIM) data. The standard comprises:

1. A schema (provided in various forms, see scope)
2. Documentation (provided in HTML, authored in Markdown)
3. Property and Quantity Set definitions (standardized definitions for an extensibility mechanism realised in the schema - provided in XML)
4. Exchange or serialization mechanisms of data files, see scope

The prevalent exchange format for IFC is the Step Physical File Format (ISO 10303-21:2002) based on the schema publication using the EXPRESS language (ISO 10303-11:2004). It is a clear-text encoding of the entity instances that make up the exchange, in which attribute values are provided as an ordered sequence of unnamed values.

Conventions

The IFC specification includes terms, concepts and data specification items that originate from use within disciplines, trades, and professions of the construction and facility management industry sector. Terms and concepts use the plain English words, the data items within the data specification follow a naming convention.

• the data item names for types, entities, rules and functions start with the prefix "Ifc" and continue with the English words in CamelCase naming convention (no underscore, first letter in word in upper case);
• the attribute names within an entity follow the CamelCase naming convention with no prefix;
• the property set definitions that are part of this standard start with the prefix "Pset_" and continue with the English words in CamelCase naming convention;
• the quantity set definitions that are part of this standard start with the prefix "Qto_" and continue with the English words in CamelCase naming convention.

buildingSMART International publishes translations of those terms and concepts into other human languages on translations.buildingsmart.org.

Model View Definitions

Official model view definitions (MVDs) exist as related specifications. The official MVD policy for IFC 4.3 currently holds 3 levels of implementation for IFC:

• Reference View
• Alignment Based Reference View
• Design Transfer view

These three MVDs can be seen as three levels of implementation for IFC 4.3. They are gradual levels adding more advanced features to the implementations. The documentation is deposited at standards.buildingsmart.org.

Architecture

The data schema architecture of IFC defines four conceptual layers, each individual schema is assigned to exactly one conceptual layer. The figure below shows the schema architecture of the IFC layered architecture.

Figure A

1. Resource layer --- the lowest layer includes all individual schemas containing resource definitions, those definitions do not include a globally unique identifier and shall not be used independently of a definition declared at a higher layer;
2. Core layer --- the next layer includes the kernel schema and the core extension schemas, containing the most general entity definitions, all entities defined at the core layer, or above carry a globally unique id and optionally owner and history information;
3. Interoperability layer --- the next layer includes schemas containing entity definitions that are specific to a general product, process or resource specialization used across several disciplines, those definitions are typically utilized for inter-domain exchange and sharing of construction information;
4. Domain layer --- the highest layer includes schemas containing entity definitions that are specializations of products, processes or resources specific to a certain discipline, those definitions are typically utilized for intra-domain exchange and sharing of information.

ifcXML

.ifcXML is a Extensible Markup Language (XML) provides enhanced readability and benefits from a broad range of software tools. ifcXML is based on the ISO standard for representation of STEP data in XML format ISO 10303-28

STEP Physical File (SPF) .ifc

STEP Physical Format (SPF or IFC-SPF) is the most widely used format for IFC in practice, which is the most compact of the formats listed that can be read as text. IFC-SPF is based on the ISO standard for clear text representation of EXPRESS data models ISO 10303-21

Reference Links

• IFC Specifications Database
• 8.9 Resource definition data schemas > IfcGeometryResource
• IFC Formats

请问需要npm和node的什么版本运行？目前在ubuntu 20.04下，安装了npm 6.14.4和node 10.19.0，都是系统命令apt安装的，运行这个系统有错误.

root@chili3d-dev:/opt/data/chili3d# npm run dev

[email protected] dev /opt/data/chili3d
npx rspack dev

yargs parser supports a minimum Node.js version of 12. Read our version support policy: https://github.com/yargs/yargs-parser#supported-nodejs-versions
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] dev: npx rspack dev
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /root/.npm/_logs/2024-04-29T05_23_15_221Z-debug.log

Any chance of being a sponsor in exchange for influence on the roadmap and hours of support?

导入stp时，可以默认stp214的方式加载吗？这样可以保留颜色

chili3d显示的没有颜色：

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Can I preview dwg directly

非常不错的一个项目，是否有计划添加约束求解器呢？

Hi, first of , congrat for this project.
Do you offer support to compile and run?
I am new in Typescript ( but I OCC skilled)
Thanks in advance

导出的文件格式或者可以参考一下DISA联盟最近推出的标准格式，可能直接使用可以减少你的设计工作量
https://www.disa.org.cn/Content-218.html